Monday, 29 June 2015

Two years after discovering the hobby of High Altitude Ballooning I have migrated from being just a passive tracker and finally completed my first flights assisted by other members of the South Kesteven ARS.

South Kesteven ARS were going to hold a special event station with the call sign GB2EGG. During the planning stage I jokingly suggested throwing
an egg in to space on board a balloon, I shouldn't have yoked...

The whole venture captured everyone's imagination, sadly putting the special event station in the shade but we certainly got a lot of publicity for the club and amateur radio in general.

Featured on front page of local paper

There was certainly a lot to learn and get organised, not only did I have to design and build the flight computer which was the easy part but I had to build the payload containers get the balloon, parachute, cord the lifting gas (Helium) and build a filler assembly as well as getting official permission from the CAA for the launch.

The cost of this venture was not insubstantial and thankfully MADHEN - The Ultimate Party Band agreed to sponsor the flight which helped greatly and I received a nice donation from fellow club member Mark Orbell (M0OBL)

Months of work and lots of last minute hitches but I was ready.

Two flights were
planned an altitude 'burst' flight with a raw egg payload with a parachute decent. The main tracker MADHEN would broadcast SSDV images and telemetry with a telemetry backup tracker EGG1 suspended below it. The second flight was a foil party balloon 'floater' with a tracker kindly donated by Steve Smith G0TDJ of ProjectAVR

Both flights flew and were a great success, unfortunately the SSDV
tracker failed early in the flight so no in flight images were received.

The main payload is pictured below before the flight resting on its side. The
Styrofoam box contained the flight computer and radio transmitter with a camera attached to the Raspberry Pi and the "flying saucer"
model which contained the egg was positioned to be visible.

As this test image shows the 'egg saucer' should have had the earth below it.

However the arduino based backup tracker which was suspended below it worked perfectly.

There were some issues with getting CAA approval because the sky was very busy on the day including the last remaining Vulcan Bomber VH-558 making its farewell flight in the area, cue jokes about the Vulcan getting scrambled... but approval was given for a morning flight, not ideal for the organisers but we were still a spectacle for the handful who were there early.

It started so well, I was receiving telemetry and image packets and then transmission stopped

However as I said the other tracker worked brilliantly and this was the final flight path as visualised in Google Earth. The ascent and decent rate and the burst altitude were exactly as planned and predicted, so I know I got the neck lift measurement right even with the high wind on the day.

Path of MADHEN/EGG1

A splashdown at sea was inevitable due to the wind conditions, hopefully it it survived the landing it may wash up on a beach somewhere and we can retrieve the images.

With what little Helium remained I was able to lightly fill and launch a foil party balloon carrying a blown egg shell as a 'floater' which made a valiant attempt to reach the continent at 6-7km high travelling at 120+km/hr where it reportably hit bad weather and was downed.

Tuesday, 9 June 2015

I have just returned from our traditional June caravanning holiday in the Lake District, last year I was buoyed with enthusiasm to have a go at some more portable operation after operating for the first time from the camp site during the 2m UKAC Contest with some encouraging results.

Indeed during the last twelve months I have done some more portable operating, but while VHF/UHF have been rewarding HF portable has been a mixed bag with at best satisfactory results, but then the same can be said of operating HF from home.

This year I planned to again operate in the 2m UKAC Contest but rather than working
from the comfort of the caravan I was going to work from some higher
ground near the camp site. Unfortunately the weather was awful with very strong winds gusting upward of 50mph and driving rain, even working from the
caravan was a no go.

So rather than enjoying this view with a microphone in hand...

... this was the how I spent the evening and as you can see Eddie was equally impressed.

When the wind and rain subsided toward the end of the week we did have some nice weather so I decided to try some HF. I had taken just the M0CVO Magitenna end-fed wire and using a 9m fibreglass pole I tried operating with it as a vertical and as a sloper both with and without counterpoises and despite receiving some very big S9+ signals on a number of bands seemed to be incapable of making myself heard, I did make a number of contacts but many reported weak signals and stood little chance of working many of the special event station pile-ups.

It wasn't helped that on the first day the radiating element connector broke, which necessitated cutting it off and stripping back the wire. I suppose in retrospect I should have been expected it as there is no strain relief on this wire, unlike the loops on the other antennas in the M0CVO range, I rectified this with a few cable ties.

I was running the Yaesu FT857-D from a leisure battery and around 30W as I
didn't wish to interfere with the TV reception as I knew most caravans would be
using wide-band antenna amplifiers because of the poor coverage. Indeed the one time I did wind the
power up to 100W one caravan mains breaker tripped out, it may have been coincidence but I didn't wish to put it to the test.

Despite the lack of performance it was great just sitting under the majestic Skiddaw and surrounding hills while I spent a few enjoyable hours operating. I even discovered one of my neighbours was also licensed, nice to meet you Joe (G4LIA)

It was frustrating from a contact point of view and I willingly accept I could be a bad workman so don't wish to blame my tools but I think some serious rethinking on a portable HF antenna is needed. I am away to Scotland next month for a week on the Isle of Skye and a week on Islay, this time in rented cottages and am hoping to make a QSO with the South Kesteven ARS on the club night.

Anyway that all has to wait as the launch of Eggsplorer-1 HAB and the GB2EGG Special Event Station are rapidly approaching.